The "McVay TEs" are used in the classic, old-school, in-line blocker/pass-catcher role, as opposed to the more "modern" hybrid TE/WR type, and the TEs are expected to block as well as they catch. So arguing how many yards (by itself) they'll get is missing the point of one of the TEs primary function. As Caley has said, the key to a running game is having strong blocking TEs, and the advantage of going against the NFL grain, is that you should be able to pick up that type of player later in the draft.
Now of course the McVay offense is starting to take over the league, so we won't be "going against the grain" for very long, but I still feel like that type of player can be found later in the draft.